Control Specification
SiBE121135
110
Function and Control
PI Control (Determine Frequency Up / Down by
∆
D Signal)
1. P control
A total of the
∆
D value is calculated in each sampling time (20 seconds), and the frequency
is adjusted according to its difference from the frequency previously calculated.
2. I control
If the operating frequency is not change more than a certain fixed time, the frequency is
adjusted according to the
Σ∆
D value.
When the
Σ∆
D value is low, the frequency is lowered.
When the
Σ∆
D value is high, the frequency is increased.
3. Limit of frequency increasing range
When the difference between input current and input current dropping value is less than 1.5
A, the frequency increasing range must be limited.
4. Frequency management when other controls are functioning
When each frequency is dropping;
Frequency management is carried out only when the frequency drops.
For limiting lower limit
Frequency management is carried out only when the frequency rises.
5. Upper and lower limit of frequency by PI control
The frequency upper and lower limits are set according to the total of S values. When the
indoor unit quiet operation commands come from more than one room or when the outdoor
unit quiet operation commands come from all the rooms, the upper limit frequency is lower
than the usual setting.